https://www.deckstainhelp.com/how-long-should-you-wait-to-stain-a-new-deck/

They are wrong about staining all sides. You only need to stain the exposed wood. There is no advantage to staining all sides, and it can actually hinder the wood by 100% sealing and not allow the wood to breathe. No stain manufacturer will suggest staining all sides for this reason.

In this video … (time stamp 2:16)

https://youtu.be/ojWLGu_Yo94?si=LEfvhetqNHHyBlKb

…the recommendation is to do it before building.  I think the problem here is I would have to leave the lumber out for a few months until it is ready to absorb the stain/sealer.  I would be using pressure treated and I live in Texas.  Has anyone done this?  Did you leave them under a tarp of some sort or in your garage?

In this video they had the factory stain/seal all 6 sides… (time stamp 12:44)

https://youtu.be/MtViNAQUn08?si=wZjCVSEoJBfwkzWq

…has anyone purchased deck boards this way? I haven’t come across any being sold this way at home depot etc.